Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /(PT|PL|ES|EN)SVG(A|U)(001|801|992|994)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(PT|PL|ES|EN)SVG(A|U)(001|801|992|994)', 'gm') const str = `PLSVGA001 PLSVGA801 PLSVGA992 PLSVGA994 PLSVGU001 PLSVGU801 PLSVGU992 PLSVGU994 PLSVGU002 PLSVGU802 PTSVGA001 PTSVGA801 PTSVGA992 PTSVGA994 PTSVGU001 PTSVGU801 PTSVGU992 PTSVGU994 PTSVGU002 PTSVGU802 ESSVGA001 ESSVGA801 ESSVGA992 ESSVGA994 ESSVGU001 ESSVGU801 ESSVGU992 ESSVGU994 ESSVGU002 ESSVGU802 ENSVGA001 ENSVGA801 ENSVGA992 ENSVGA994 ENSVGU001 ENSVGU801 ENSVGU992 ENSVGU994 ENSVGU002 ENSVGU802 ----------- PTSVZC001 `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions